DBRB-V Transformer Winding Deformation Tester

Product Introduction

DBRB-IV Transformer Winding Deformation Tester can make accurate diagnosis on the transformer internal fault based on the measurement of the characteristic parameters of transformer windings inside, using the frequency response analysis (FRA) method developed and improved by the developed countries.

After the completion of design and manufacture of transformers, the coils and internal structure are finalized, so for the coil of a multi-winding transformer, if the voltage level and winding method are the same, the corresponding parameters (Ci, Li) of each coil shall be determined. Therefore, the frequency characteristics response of each coil also will be determined, so the frequency spectrums of the corresponding coils of three phases are comparable.

During the test of transformer, in case of inter-turn, inter-phase short circuit, or relative coil displacement caused by collisions during transport, as well as coil deformation resulted from electromagnetic tension during operation under short circuit and fault conditions, the distribution parameters of transformer windings will change, which thereby in turn affects and changes the transformers’ original frequency domain characteristics, namely the frequency response change in magnitude and the resonant frequency points shift. The transformer winding tester developed according to the response analysis method is the novel NDT equipment for detecting transformer internal fault. It applies to the detection of internal structure fault in 63kV-500kV power transformers.

DBRB-IV Transformer Winding Deformation Tester is to determine the degree of changes in internal windings of the transformer based on the quantity of change, magnitude and region affecting change and tendency of frequency response change which are quantized from the response changes in different frequency domains of transformer’s internal winding parameters, and then it can help you determine whether the transformer has been severely damaged, or need a major overhaul in accordance with the measurement results.
For the transformer in operation, no matter whether the frequency domain characteristic drawing is saved, by comparing the differences between the inter-coil characteristic spectra of faulted transformer, it can determine the extent of the failure as well. Of course, if you have saved the original transformer windings feature drawings, it will be simpler to provide a precise basis for operating conditions, post-fault analysis and maintenance overhaul of the transformer.

Product Features

1. Acquisition and control using high-speed, highly integrated microprocessor.
2. Communication USB interface used between a laptop and instrument.
3. Wireless WIFI interface (optional) used between the laptop computer and instrument.

4. Hardware adopts dedicated DDS digital high-speed scanning technology (USA), which can accurately diagnose the faults like winding distorted, bulged, shift, tilt, inter-turn short-circuits deformation and inter-phase contact short-circuit.
5. High-speed dual-channel 16-bit A/D sampling (in field test, move tap changer, and the wave curve shows obvious change) .
6. Signal output amplitude is adjusted by software, and the peak value of amplitude is ± 10V.
7. The computer will automatically analyze the test results and generate electronic documents (Word)

8. The instrument has dual measurement features: linear frequency scanning measurement and segment frequency scanning measurement, compatible with measurement mode of two technical groups in China

9. The amplitude-frequency characteristics are in line with the national technical specifications on amplitude-frequency characteristics tester. X-coordinate (frequency) has linear indexing and logarithmic indexing, so you can print out the curve with linear indexing and logarithmic indexing. The user can choose either according to actual needs.
10. Automatic test data analysis system,
Compare between A, B, C -phases in winding similarity comparison, and the analysis results are:
① excellent consistency
② good consistency
③ poor consistency
④ rather poor consistency

Compare winding deformation by calling the original data and comparing it with the current data of the same phase, namely A-A, B-B, C-C, and the analysis results are:
① normal winding
② mild deformation
③ moderate deformation
④ severely deformation

11. Word electronic document can be automatically generated for saving and printing.

12. The instrument can fully meet the technical requirements of electricity standard DL/T911-2004 "Transformer winding deformation frequency response analysis".

Technical Specifications
Scan mode:
1. Linear scanning distribution
Scanning measurement range: (10Hz) - (10MHz) 40000 scanning point, resolution 0.25kHz, 0.5kHz and 1kHz
2. Segment frequency scanning measurement distribution
Frequency scanning measurement range: (0.5kHz) - (1MHz), 2000 scanning points;
(0.5kHz) - (10kHz)
(10kHz) - (100kHz)
(100kHz) - (500kHz)
(500kHz) - (1000kHz)

Other technical parameters:
1. Amplitude measurement range: (-120dB) to (+20 dB)
2. Amplitude measurement accuracy: 0.1dB
3. Scanning frequency accuracy: 0.01%
4. Signal input impedance: 1MΩ
5. Signal output impedance: 50Ω
6. Signal output amplitude: ± 20V
7. Test repetition percent: 99.9%
8. Measuring instruments dimensions (LxWxH) 300X340X120 (mm)
9. Instrument’s aluminum box size (LxWxH) 310X400X330 (mm)

10. Overall weight: 10Kg